Human CDCP1 ((CUB domain containing protein 1, B345, CD318, SIMA135, TRASK; SEQ ID NO: 1 and variants with mutation R525Q (i.e. replacement of Arginine (R) with Glutamine (Q) at amino acid position 525 of SEQ ID NO: 1) and/or mutation G709D (i.e. replacement of Glycine (G) with Aspartic acid (D) at amino acid position 709 of SEQ ID NO: 1)) is a transmembrane protein containing three extracellular CUB domains. This protein is found to be overexpressed in colon and lung cancers. Its expression level is correlated with the metastatic ability of carcinoma cells. It has been shown to be tyrosine phosphorylated in a cancer cell line. (WO 2002/004508; Scherl-Mostageer, M. et al., Oncogene 20 (2001) 4402-8; Hooper, J. D., et al., Oncogene 22 (2003) 1783-94; Perry, S. E. et al., FEBS Lett. 581 (2007) 1137-42; Brown, T. A., J. Biol. Chem. 279 (2004) 14772-14783; Ota, T., et al., Nat. Genet. 36 (2004) 40-45). Alternatively spliced transcript variants encoding distinct isoforms have been reported.
WO 2002/004508 refers to CDCP1 as tumor associated antigen B345. WO 2004/074481 relates to CDCP1 as glycoprotein antigen SIMA135 expressed in metastatic tumor cells. WO 2005/042102 relates to CDCP1 as protein involved in ovarian cancer. WO 2007/005502 relates to methods and compositions for treating diseases targeting CDCP1.
US 2004/0053343 (and Conze, T. et al., Ann. N.Y. Acad. Sci. 996 (2003) 222-6 and Buhring, H. J. et al., Stem Cells 22 (2004) 334-43) relates to CDCP1 antibodies for identifying and/or certain cell stem cell populations.